CPT® Code 83701

Lipoprotein, blood; high resolution fractionation and quantitation of lipoproteins including lipoprotein subclasses when performed (eg, electrophoresis, ultracentrifugation)

The CPT® Code 83701 refers to a specialized blood test that measures lipoprotein levels through high resolution fractionation and quantitation of lipoproteins, including their subclasses when necessary. Lipoproteins are complex biochemical structures composed of lipid molecules, which are fats, bound to proteins. These structures play a crucial role in the transport of lipids throughout the body via the bloodstream. Lipoproteins can vary significantly in size and density; they can be large and less dense, where the fat content exceeds the protein content, or small and more dense, where the protein content surpasses the fat content. The origins of these lipoproteins can be either exogenous, derived from dietary fats, or endogenous, produced by the liver. To perform this test, a blood sample is collected, typically through a procedure known as venipuncture, which is separately reportable. The process of high resolution fractionation involves advanced techniques such as quantitative electrophoresis or ultracentrifugation. In quantitative electrophoresis, an electrical field is applied to separate the lipoprotein molecules, which are subsequently stained and quantified using a densitometer. Alternatively, ultracentrifugation separates lipoproteins based on their hydrated densities, utilizing salts to fractionate them. During this process, the specimen is centrifuged, allowing for the separation of very low density and low density lipoproteins from high density lipoproteins, with the amounts of each type being quantified. This detailed analysis is essential for assessing and managing conditions related to elevated triglyceride levels and cardiovascular disease risk, particularly in patients with diabetes.